1. Field of the Invention
The invention relates to a track-bound mobile crane having a vertically-adjustable carrying device that is arranged on the vehicle frame. A guide carrier is attached to the carrying device so that the guide carrier extends in the longitudinal direction of the mobile crane and has a longitudinally movable trolley of a lifting unit.
2. Description of the Prior Art
Track-bound mobile cranes are used for rail and bridge construction, among other purposes, as well as for rescue work. These cranes must be highly maneuverable even under cramped working conditions. Known devices of the generic type are equipped with short rigid guide carriers, on which it is possible to move trolleys supported with lifting units in the longitudinal direction. The pathways of these trolleys correspond approximately to the length of the vehicle, which results in the working area of the known devices being limited. In particular, it is difficult to pick up and set down loads beside the track of the mobile crane, because the rigid arrangement of the trolley pathway limits the maneuverability of the lifting device.
Track-bound mobile cranes are also known in which upper carriages with crane jibs are arranged rotatably on the center of the lower carriage, as in mobile cranes that can travel on the street. However, the use of such cranes is often difficult or impossible because of conditions at the work site, danger to traffic on neighboring tracks, or overhead contact wires. Furthermore, the handling of loads and the performing of work in tunnel regions, for example, especially on single-track lines, is possible only with great difficulty using known mobile cranes.